If you’re gonna crib, crib from the best and they don’t come a whole lot better these days than David Weber. I have the first 9 of the “Safehold” series and the 10th is out – for FIFTEEN BUCKS! Love the series but these days $15 is kinda steep for a retiree living on a fixed income. Wish Weber (and a lot of other established authors) would let their books be available on Kindle Unlimited. For 9 bucks a month I can borrow as many books as I wish.

So, these ‘detectors’ only detect energy weapons. They’d miss nearly any weapon the Cats use.
Heinlein wrote about a hierarchy of patriotism, positing that the lowest form was to oneself, then to one’s family, then community, then nation, then species, then the whole world. Each more advanced and superior to the previous. Sounds like these policemen are at the highest level, their loyalty belonging to Something higher than their species.